Does my site often goes down because of the theme?

Hi, I’am using this theme for my wordpress site. For some reasons, my site loading speed is very slow. I have tried all the steps to speed up the site. But nothing worked. Server team says that memory is critical.

Additional Info: Usage: real 95% (3654/3831 MB), buffer: 10 MB, cache: 47 MB, swap: 35% (720/2048 MB)

They doubt it might be because of the theme now. . This is my site. Can you please check if there is any issue on the theme side.?

Thank You!